Duplicator



Julyl 26, 1927. 1,636,780

E. I ICHTENSTEIN DUPLI GATOR Filed sept. 2s, 1925 s sums-smul July 26, 1927. 1,636,780

E. LICHTENSTEIN DUPLICATOR Filed Sept. 26, 1925 3 Sheets-Shut 2 Fig# July 25 1927' E. LlcH'rr-:NsTExN DUPLI CAT OR Filed Sept. 26, 1925 3 Sheets-Shoot 3 Fly 7.

Patented July 26, 1927.

UNI-TED STATES "PATENT OFFICE.

EDMUND LICHTENSTEIN, 0F BERLIN, GERMANY, ASSIGNOR TO DEUTSCHE MASCHU- ENBAU- UND VERTRIEBS-GESELLSCHAFT M. B. H., OF BERLIN, GERMANY, A. FIRM.

DUI'LICATOB.

Application med september'as, 1925, semina. 58.908, and in Germany october 1e, 1924.

This invention relates to duplicators more particularly applicable. for office purposes, which operate on the oit-set principle, in that they print from a form cylinder or roller, preferablycarrying a thin pliant metal printing vform according to German Patent No. 350,484, on to a rubber cylinder or roller and from the latter onto the paper supported by a printing cylinder, roller or the like.

In such oliice duplicators wherein, as a rule, only a comparatively small number of copies are' printed from a printing form, so that a frequent changing of the printing form is necessary, a considerable disadvantage resides in that the frequent removal of the ink still remaining from the previous text from the rubber cylinder, is difficult owing to the fact that even in the most convenient arrangements the rubber cylinder, is

located more or less inaccessibly underneath the impression and printing cylinders.

According to the present invention this drawback is eliminated whilst retaining the cylinder arrangement above referred to, in that the position of one of the three cylinders of the machine above referred to may be changed in such a manner that the rubber cylinder becomes readily accessible.

In such duplicators the impression c linder is, as a rule, provided on its perip ery with a groove or the like for clamping the pliant printing form thereon, and usually the rubber cylinder is also provi-ded with similar securing means for securing its divided covering consisting of a rubber plate placed around it. These securing means on the impression cylinder and on the rubber cylinder must always pass opposite one another during rotation of the cylinders when the machine is in operation, and when the duplicator prints on a web of paper which is automatically cut into sheets after being printed, the cut must always be effected at the point of the paper exactly corresponding `with these securing means.

According to the invention precautions are provided in order that not only when releas` ing, as is well 'known in the case of machines without cutting mechanism, but also when the movable cylinder is moved, withdrawn, or the like to a relativelylarge extent, and when rotating the rubber cylinder for the purpose of cleaning, the operative enconstruction areV shown diagrammatically` and in which y Fig. l is a side elevation of of a duplicator.

Fig. 2 is a side elevational view illustrating the movement of one of the rollers.

Fig. 3 is a similar view of a modified arrangement.

Fig. 4 is a perspective view of the rollers according to Fig. 1.

Fig. 5 is a similar perspective view showing the driving arrangement for the rollers.

Fig. 6 is a similar perspective view showing a support for the movable cylinder.

Fig. 7 1s aperspective view showing a tensioning device.

The machine is provided with a rinting cylinder or roller a, a rubber cylmder or roller b and an impression cylinder or roller c. The paper d passes from a supply roll between 'the cylinders b and c, over the cylinder c, under a weighting roller 6 and through the cutters 4 to the delivery device.

The printing cylinder co-operates with a moistening device consisting, for example, of twov rollers 2, and an inking mechanism consisting, for example, of four rollers 3.

According to the invention the rubber cyl-v inder b (Fig. 2) is carried byan oscillatory frame e adapted to swing about the axis of the printing cylinder a so that the cylinder the main parts b can be swung from the full line position into the dotted line position in Which it can be locked in any suitable manner. In this position the rubber cylinder b is freely exposed so that the text or ink from the previous printing operation can be conveniently removed therefrom.

VIn the construction according to Fig. 3 the position of the printing cylinder a is adapted to be changed instead of that of the rub er cylinder b. The dotted line in Figure 3 shows the printing cylinder in the operative position in which it leaves the rubber cylinder b more or less inaccessible. If, however, the cylinder a is moved or swung into the full line position the cylinder b becomes accessible.

The machine is driven from the cylinder a which by means of the toothed wheels lc, l and m drives the cylinder c and by means of the toothed wheels h, 11 the cylinder b.

If the cylinder b is moved from the full line position in Fig. 2 into the dotted line position the toothed wheels h and z' remain in engagement so that the accurate co-operation, above referred to, between the securing means of the cylinder coverings and the cutting device 4 is retained, the latter being adapted to be positively coupled to the main Idrive in any suitable manner.

For the purpose of tightening or for producin the operative pressure between the cylin ers play is provided in their bearings and is compensated for by a tensioning device. For .this purpose, accordin to the invention onl so much play g is al owed by longitudinal oles, by reason of the mounting of the frame e on the axis of the cylinder a, that, when loosening, the toothed wheels k and z' cannot be disengaged from one another.

As the drive of the rubber cylinder b from the rinting cylinder a is effected by means of t e tooth wheel gear h, i, which is independent of the tooth wheel gear lc, Z and m driving the impression cylinder c and the cutting mechanism 1l, the cutting mechanism 4 cannot be brought out of step by movingthe rubber cylinder in and out.

The frame e is held in the o erative position b sup ortin levers p w ich engage under t e en s f t e shaft of the cylinder b and are supported by a shaft q which is adapted to be raised and lowered by the tensioning device to be hereinafter described.

These supporting levers, according to the invention, are also used for automatically catching or arresting the cylinder b when it swings from the dotted position shown in Fig. 2 back into the full line position. For this purpose the levers p are not rigidly clamped on the shaft g but are adapted to have a limited yieldn movement in a. clockwise direction (Fig. 6 in the manner of the known slip pawls. If therefore on the return movement of the cylinder b the stub shafts thereof abut against the levers p from the rear (left) these yield and move into the dotted position shown in Fig. 6 whereupon, by means o1 springs not shown, they im- Inediately swing back under the axis of the cylinder b into the full line position and now ret-ain the cylinder.

-It will be understood that the levers p could also be keyed to the shaft g which would then have to be spring actuated. Naturally separate catch members could be used instead of the levers p.

In order that when` moving the cylinder b about the cylinder a preparatory to printing-particularly when in ing the printing cy inder and rotating the corresponding -between the roller a which has already been designated as the driving roller, and the train of gears beginning with the gear k which controls the operation of the pa er feed-mechanism and the impression .cyhn er.

In order that the correct cooperat1onwill not be affected in spite of this only a single hole 7' is rovided in the toothed wheel c or the coup lng pin n which couples the cylinder a to the toothed wheel L'. lVhen the Jin enga es with this hole the correct angu ar relation of the cylinder is obtained.

The coupling pin n is controlled by a stationary pusher s and may also be spring ac# tuated so that when coincident .with the hole r it will engage therewith automatically.

According to the invention provision 1s made so that the proper yielding working pressure between the cylinders is effected automatically as soon a@ the clutch n is engaged. For this purpose a cam t, for example, is provided which is ositively driven by the toothed wheel m, and), as soon as this occurs the pressure lever u xFig. 7) swings in a clockwise dilection. T e pin o of the lever u then presses the shaft and'thus the cylinder b upwardl until t e lever u is locked in the adjuste position 4by the catch c.

It will be understood that both ends of the shaft q are raised uniformly for which purpose a second lever u or transmission gear may be provided.

4For ad'ustln the necessary pressure of the cylin er to raised into position without additional trouble and to providefor this pressure also in the case of wear, the pressure pin o is actuated by a tension spring w.

1. A duplicator operating upon the olset principle comprising an impression-cylinder,

a printmg cylinder, a rubber cylinder located beneath said first mentioned cylinders when the machine is in operation, said c linders being bperatively connected y toothed gearm ,means whereby one of said cylinders may `moved to facilitate access to said rubber cylinder, a cutting mechanism, means for permitting play between the axes of said cylinders, means for taking up this pla the amount of said play being of limite extent so that said toothed gear connec-l tion between said cylinders is maintained even when said means for taking up said play is released and means whereby the toothedwheel connection is also maintained when eectin the movement which renders the rubber cy inder conveniently accessible. 2. `A duplicator operating upon the offset principle comprising an impressioncylinder, a printing cylinder, a rubber cylinder located beneath saidlrst mentioned cylinders when the machine is in operation, said im- 1 0 pression and rubber cylinders being operatively connected by toothed gearing, ymeans including a frame rotatably mounted about the axis of one of the cylinders and carrying another ot' said cylinders for rendering said rubber cylinder accessible, a cutting mechanism, means on said frame for permitting play between the axis of the cylinder carried by said frame and its associated cylinder, means for taking up said play, the amount of said play being ot' limited extent so that the toothed gear connection between said movable cylinder and its associated cylinder is maintained even when said means for taking up said play is released and means whereby the toothed gear connection is also maintained when effecting the movement which renders the rubber cylinder accessible.

3. A duplicator operating upon the offset principle comprising an impression cylinder, a printing cylinder, and a driving connection therebetween a rubber cylinder located beneath said first mentioned cylinders when the machine is in o eration, means whereby one of said cylinders may be moved so that the rubber cylinder is made conveniently accessible ,and means for driving said movable cylinder from its associated cylinder independently of the drive between said last mentioned cylinder and the other cylinder whereby a determined relative arrangement between the other cylinders is maintained when the movable cylinder carried by said frame is moved.

4. A duplicator operating upon the offset principle comprising an impression cylinder, a printing cylinder, and a driving connection therebetween a rubber cylinder located beneath said first mentioned cylinders when the machine is in operation, means including a frame rotatably mounted about the axis of,

one of the cylinders and carrying another of said cylinders and a gear wheel connection between said last mentioned cylinders which is independent of the drive connection between the other cylinders whereby a determined relative positioning is maintained between the other cylinders when the movable cylinder carried by said frame is moved.

5. A duplicator operating upon the offsetprinciple comprising an impression cylinder, a printing cylinder, and a driving'connection therebetween a rubber cylinder located beneath said first mentioned cylinders when the machine is in operation, means whereby one of said cylinders may be swung about another cylinder to facilitate access to said rubber cylinder, a toothed gear connection between the cylinder that is swung and the .cylinder about which it is swung independent of the drive between last mentioned cylinder and the impression cylinder, a cutting mechanism, means for permitting play between the axes of said cylinder that is swung and its associated cylinder, a device for tal;- ing up said play, the amount of play being such that said toothed gear connect-ion is maintained even when said device for taking up said play is released and when etiecting the movement which renders the rubber cylinder' conveniently accessible.

(i. A duplicator operating upon the otlset principle comprising an impression cylinder, a printinnr cylinder, and a driving connection therebbetween a rubber cylinder located beneath said first mentioned cylinders .when the machine is in operation, means including a frame rotatably mounted about the axis of one of the cylinders and carrying another of said cylinders, a toothed gear connection between the cylinder carried by the trame and the cylinder about which it swings independent of the drive between the last named cylinder and the impression cylinder, a cutting mechanism, means on said frame for permitting play between the axis of said swingable cylinder and. its associated cylinder, means for taking up said play, the amount of play being such that said toothed gear connection is maintained even when said, means for taking up said play is released and means whereby said connection is also maintained when effecting the movement which renders the rubber cylinder accessible.

7. A duplicator operating upon the otiset principle comprising an impression cylinder, a printing cylinder, a rubber cylinder located beneath said first mentioned cylinders when the machine is in operation, meanswhereby one of said cylinders may be moved to facilitate access to said rubber cylinder, a cutting mechanism, means for permitting play between said movable cylinder and its associated cylinder means for taking up .said play, a toothed gear connection between said last mentioned cylinders maintained in engagement even when said means t'or taking up said play is released, and when the movable cylinder is moved to give access to the rubber cylinder, levers for supporting the movable cylinder and means for causing said levers to bring said cylinder into operative association with its associated cylinder.

8. A duplicator operating upon the oiiset principle comprising an impression cylinder, a printing cylinder, a rubber cylinder located beneath said iirst mentioned cylinders when the machine is in operation, means whereby one of said cylinders may be moved so that the rubber cylinder is conveniently accessible and means for automatically latehing said movable cylinder adjacent its operative position prior to its being moved into operative relation with its associated cylinder.

9. A duplicator operating upon the oii'set principle comprising an impression cylinvau der, a printing cylinder, a rubber c linder located beneath said first mentions cylinders when the machine is in operation, means including a frame rotatably mounted about the axis of one of said cylinders and carryin another of said cylinders for moving said last mentioned cylinder to facilitate access tosaid rubber cylinder and means for automatically latching said frame with the movable cylinder adjacent its operative position.

10. A duplicator operating upon the oliset princi-ple comprising an impression cylinder, a printing cylinder, a rubber cylinder located beneath said irst mentioned cylinders when the machine is in operation, means permitting movement of one of. said cylinders to facilitate access to the rubber cylinder, a gear connection between said movc able cylinder and one of said other cylinders which is independent of the gear connection between said othei` cylinder and the remaining cylinder and a releasable clutch interposed in said last mentioned gear connection. s

1l. A duplicator operating upon the otset principle comprising an impression cylinder, a printing cylinder, a rubber cylinder located beneath said first mentioned cylinders when the machine -is in operation, means permitting movement of one of said cylinders to facilitate access to the rubber cylinder, a gear connection between said movable cylinder and one of said other cylinders which is independent of a gear connection between said other cylinder and the remaining cylinder and a releasable clutch which can only engage in a single determined relative rotary osition of the impression cylinder and ru ber cylinder interposed in said last mentioned gear connection.

12. -A duplicator operating upon the offset principle comprising an impression cylinder, a printing cylinder, a rubber cylinder located beneath said tirst mentioned cylinders when the machine is in operation, means permitting movement of one of said cylinders to facilitate access to said rubbercylindcr, a gear connection between said movable cylinder and one of said other cylinders which is independent of a gear connection between said other cylinder and the remaining cylinder, a clutch device in said second mentioned gear connection means for tensioning or moving said movable cylinder into operative association with its associated cylinder and means for automatically tensioning the movable cylinder as soon as the clutch device'is engaged.

In testimony whereot` I have affixed my signature. i EDMUND -LICHTENSTEIN 

